The objective of these studies is to investigate the absorption, distribution and pulmonary toxicity of several novel chemicals used in the semiconductor and photovoltaic industries. The first 3 chemicals to be evaluated are copper-indium diselenide (CIS), copper-gallium diselenide (CGS) and cadmium telluride (CdTe). These chemicals were selected because of their increasing use, the potential for inhalation exposure, and the lack of pharmacokinetic/toxicity data. In an initial range-finding study, female Sprague-Dawley rats were administered 2.5, 5, 10, or 20 mg CIS per animal by intratracheal instillation, and sacrificed 72 hours later. Lung weights were significantly increased in all treatment groups. Evaluation of bronchoalveolar lavage fluid (BALF) cellularity revealed a significant influx of neutrophils (PMNs) at dose levels of 5 mg and above. Studies are in progress to follow the progression of CIS pulmonary toxicity at lower doses and a longer duration, as well as to investigate the pharmacokinetics of CIS. Comparative studies will be conducted with CGS and CdTe.